<!-- 商家销量统计的横向柱状图 -->
<template>
  <div class="com-container">
    <div class="com-chart" ref="seller_ref"></div>
  </div>
</template>

<script>
import { mapState } from "vuex";
export default {
  name: "Seller",
  data() {
    return {
      chartInstance: null,
      allData: null,
      currentPage: 1, //当前显示的页数
      totalPage: 0, //一共有多少页
      timerId: null, //定时器标识
    };
  },

  components: {},

  computed: {
    ...mapState(["theme"])
  },
  watch:{
    theme(){
      this.chartInstance.dispose()
      this.initChart()
      this.screenAdapter()
      this.updateChart()
    }
  },
  created() {
    this.$socket.registerCallBack("sellerData", this.getData);
  },

  mounted() {
    this.initChart();
    // this.getData();
    this.$socket.send({
      action: "getData",
      socketType: "sellerData",
      chartName: "seller",
      value: "",
    });
    window.addEventListener("resize", this.screenAdapter);
    // 在页面加载完成的时候,主动进行屏幕的适配
    this.screenAdapter();
  },

  destroyed() {
    clearInterval(this.timerId);
    // 组件销毁的时候,需要将监听器取消掉
    window.removeEventListener("resize", this.screenAdapter);
    this.$socket.unRegisterCallBack("sellerData");
  },

  methods: {
    //   初始化echartInstance对象
    initChart() {
      this.chartInstance = this.$echarts.init(this.$refs.seller_ref, this.theme);
      //   对图表初始化配置的控制
      const initOption = {
        title: {
          text: "▎商家销售统计",
          left: 20,
          top: 20,
        },
        grid: {
          top: "20%",
          left: "3%",
          right: "6%",
          bottom: "3%",
          containLabel: true, //距离是包含坐标轴上的文字
        },
        xAxis: {
          type: "value",
        },
        yAxis: {
          type: "category",
        },
        tooltip: {
          trigger: "axis",
          axisPointer: {
            type: "line",
            z: 0,
            lineStyle: {
              color: "#2D3443",
            },
          },
        },
        series: [
          {
            type: "bar",
            label: {
              show: true,
              position: "right",
              textStyle: {
                color: "white",
              },
            },
            itemStyle: {
              //   指明颜色渐变的方向
              // 指明不同百分比之下颜色的值
              color: new this.$echarts.graphic.LinearGradient(0, 0, 1, 0, [
                {
                  offset: 0,
                  color: "#5052EE",
                },
                {
                  offset: 1,
                  color: "#AB6EE5",
                },
              ]),
            },
          },
        ],
      };
      this.chartInstance.setOption(initOption);
      //   对图表对象进行鼠标事件监听
      this.chartInstance.on("mouseover", () => {
        clearInterval(this.timerId);
      });
      this.chartInstance.on("mouseout", () => {
        this.startInterval();
      });
    },
    //   获取服务器的数据
    getData(res) {
      // this.$axios({
      //   method: "get",
      //   url: "seller",
      // })
      //   .then((res) => {
      //     this.allData = res.data;
      //     this.allData.sort((a, b) => {
      //       return a.value - b.value; //从小到大的排序
      //     });
      //     //每五个元素显示一页
      //     this.totalPage =
      //       this.allData.length % 5 === 0
      //         ? this.allData.length / 5
      //         : this.allData / 5 + 1;

      //     this.updateChart();
      //     //   启动定时器
      //     this.startInterval();
      //   })
      //   .catch((err) => {
      //     console.log(err);
      //   });
      this.allData = res;
          this.allData.sort((a, b) => {
            return a.value - b.value; //从小到大的排序
          });
          //每五个元素显示一页
          this.totalPage =
            this.allData.length % 5 === 0
              ? this.allData.length / 5
              : this.allData / 5 + 1;

          this.updateChart();
          //   启动定时器
          this.startInterval();
    },
    // 更新图表
    updateChart() {
      const start = (this.currentPage - 1) * 5;
      const end = this.currentPage * 5;
      const showData = this.allData.slice(start, end);
      const sellerNames = showData.map((item) => {
        return item.name;
      });
      const sellerVlaue = showData.map((item) => {
        return item.value;
      });
      const dataOption = {
        yAxis: {
          data: sellerNames,
        },
        series: [
          {
            data: sellerVlaue,
          },
        ],
      };
      this.chartInstance.setOption(dataOption);
    },
    startInterval() {
      if (this.timerId) {
        clearInterval(this.timerId);
      }
      this.timerId = setInterval(() => {
        this.currentPage++;
        if (this.currentPage > this.totalPage) {
          this.currentPage = 1;
        }
        this.updateChart();
      }, 3000);
    },
    // 当浏览器的大小发生变化的时候,调用的方法,来完成屏幕适配
    screenAdapter() {
      const titleFontSize = (this.$refs.seller_ref.offsetWidth / 100) * 3.6;
      //   分辨率大小相关的配置项
      const adapterOption = {
        title: {
          textStyle: {
            fontSize: titleFontSize,
          },
        },
        tooltip: {
          axisPointer: {
            lineStyle: {
              width: titleFontSize,
            },
          },
        },
        series: [
          {
            barWidth: titleFontSize,
            itemStyle: {
              // 圆角效果
              barBorderRadius: [0, titleFontSize / 2, titleFontSize / 2, 0],
            },
          },
        ],
      };
      this.chartInstance.setOption(adapterOption);
      //   手动调佣图表对象的resize,才能产生效果
      this.chartInstance.resize();
    },
  },
};
</script>
<style lang='less' scoped>
</style>